Do all over-revs record in ECU including downshift over-revs What is shown on an over-reved engine?

Yes, most modern Engine Control Units (ECUs) record over-rev events, including those caused by downshifts. An over-rev occurs when the engine operates beyond its maximum RPM limit, which can lead to potential damage. In the event of an over-rev, the ECU may log the maximum RPM reached, the duration of the over-rev, and the specific conditions under which it occurred, such as throttle position and gear selection. This data can be analyzed for diagnostics and performance tuning.